This application continues the first study to assess longitudinally the long-term effects of prenatal tobacco and other substance use on the children of teenage parents. Tobacco use during pregnancy and the increased rate of difficulties related to teenaged motherhood both predict a high risk for developmental problems in the offspring of adolescents. Yet, to date, the investigators have little information about these risk factors and the interactions between them. They are currently following a unique cohort of over 400 pregnant teenagers who were interviewed systematically concerning their trimester-specific tobacco and other substance use during pregnancy, at delivery, and 6 years after their children were born. Preliminary analysis of behavioral, cognitive, and growth outcomes from the 6-year-old children show that tobacco exposure from three different sources (prenatal, passive and mother's current) significantly affect child outcomes. Children who were exposed prenatally to tobacco had more attention problems, higher activity levels, and were more impulsive and more emotional. Prenatally exposed children had higher body mass indices and skinfold thickness. Passive exposure to current tobacco smoke was related to poorer receptive language abilities. Children of mothers who were current smokers had shorter stature. In this competing renewal application, the investigators will assess the children at age 10. At this age, more complex cognitive and neuropsychological dimensions of functioning can be assessed. Strengths of this study include a detailed assessment of all substances, measurement of potential confounding factors, including environmental factors, a comprehensive child assessment battery, and excellent retention rates. A further strength of this study is the ability to compare prenatal tobacco effects on 10-year-old offspring of teenagers with the effects on a demographic similar cohort of 10-year-old children of adult parents. The specific aims are to: 1) examine the long-term effects of prenatal tobacco exposure on growth, cognitive, behavioral and neuropsychological outcomes on children of adolescent mothers, 2) examine the long-term effects of prenatal tobacco exposure on child outcomes considering potential moderating and mediating effects of the environment and of factors from earlier phases, and 3) compare the relations of prenatal tobacco exposure and child outcomes between offspring of teenaged parents and offspring of adult age parents.